Guide to Gems & Precious Stones



Gems and precious stones are generally beautiful minerals that can be cut and polished to create jewelry items. Some gems are not classified as minerals, and these include lapis-lazuli, amber, and jet. The values of gems and precious stones are determined by their luster, clarity, and rarity. Gemstones that are highly valued include diamonds, rubies, sapphires, and emeralds.

Gemstones Information and Gem Pictures

Almost all the gems and precious stones that have been found were discovered beneath the surface of the Earth. Different types of gemstones originate from different formation processes. Many gemstones are formed by the reaction between underground minerals and water. A solution will be created when minerals dissolve in water, and this solution will become a gemstone when it solidifies. When minerals that are rich in silica are dissolved in water, opals, amethysts, and agates will be formed, and minerals that are rich in copper will create turquoise, malachite, and azure. Other geological processes that lead to the creation of gemstones are crystallization in magma, and the formation of metamorphic rocks and olivine. Diamonds are formed by extreme heat and pressure in the mantle of the Earth, and they are brought to the surface by volcanic eruptions.

Gem Formation
Formation of Gems

There are many types of gems and precious stones, and they are divided into several major categories. Diamond is the hardest natural substance that has been found on Earth, and it is the most highly valued of all gemstones. The second hardest type of gemstone is the corundum, and gems that fall into this category are rubies and sapphires. Chrysoberyls, such as alexandrite and cat’s eye, are also very hard gemstones, and they are admired for their abilities to change color when exposed to different lighting. Onyx, citrines, amethysts, and carnelians are quartz gemstones, and they come in many different colors. Beryls share certain similarities with quartz stones and chrysoberyls, and they are transparent when they are in their simplest form. Aquamarines and emeralds are colored variants of beryls. Other major types of gemstones are jade, feldspar, and organic gemstones, which include amber and pearl.

Types of Gemstones

Gemstone dealers and enthusiasts have to understand certain gem-related terms to communicate intelligently about gemstones. These terms will help them provide better information about the characteristics, conditions, and values of gemstones. Some of the basic terms include “carat”, which is the weight of a gemstone; “density”, which measures the ratio of a gemstone’s weight to its volume; “hardness”, which refers to a gemstone’s resistance to scratches and abrasion; “luster”, which is a gemstone’s ability to reflect light; and “inclusions”, which refers to substances that are found inside a gemstone, such as liquids, bubbles, or other minerals.

Gems and precious stones have been regarded as precious objects since thousands of years ago. While some cultures in the past used them for the creation of jewelry items, others used them as healing objects. Even up to today, many people believe that gems and precious stones have metaphysical and healing powers.

Gems and Precious Stones Resources:
History of Gemstones
Natural Gemstones
Wholesale Jewelry
International Gem Society
Gemological Institute of America